CVE-2026-21860

Werkzeug is a comprehensive WSGI web application library. Prior to version 3.1.5, Werkzeug's safe_join function allows path segments with Windows device names that have file extensions or trailing spaces. On Windows, there are special device names such as CON, AUX, etc that are implicitly present and readable in every directory. Windows still accepts them with any file extension, such as CON.txt, or trailing spaces such as CON. This issue has been patched in version 3.1.5.

CVSS

No CVSS.

References

Link	Resource
https://github.com/pallets/werkzeug/commit/7ae1d254e04a0c33e241ac1cca4783ce6c875ca3
https://github.com/pallets/werkzeug/security/advisories/GHSA-87hc-h4r5-73f7

Configurations

No configuration.

History

08 Jan 2026, 19:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-08 19:15

Updated : 2026-01-08 19:15

NVD link : CVE-2026-21860

Mitre link : CVE-2026-21860

CVE.ORG link : CVE-2026-21860

JSON object : View

Products Affected

No product.

CWE

CWE-67

Improper Handling of Windows Device Names

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